Since I can't seem to figure out how to attach this to ID 1861812, I'll attach it here.
This adds allowed_quota() calls around every $tQuota in create-mailbox.php
Tested a number of cases and it appears to behave fine for me.
Patch for SF: 1861812
Since you didn't respond on #postfixadmin, I'll paste my questions/feedback here:
[23:23] <cboltz> supa_user: I'm just reading your patch
[23:23] <cboltz> and found something that looks like a bug to me
[23:24] <cboltz> you should probably use = allowed_quota($fDomain, 0) everywhere
[23:24] <cboltz> because a not-yet created mailbox does not use any quota yet ;-)
[23:27] <cboltz> I also think you should not change the "$tQuota = $fQuota" in line 139
[23:27] <cboltz> because that line is meant to give the user the values he entered so he can correct them
[23:28] <cboltz> IMHO it shouldn't be changed magically
[23:29] <cboltz> (we also don't change other fields if they contain invalid values)
[23:30] <cboltz> do you agree or did I overlook something? ;-)
I agree with your changes. Adjusted patch attached.
Commited to SVN trunk r1201.